A Coupling-Insensitive X-Type IPT System for High Position Tolerance

The output characteristic of an inductive power transfer (IPT) system is highly susceptible to variations in magnetic coupling. In this article, a primary-side X-type compensation topology is proposed to acquire stable output characteristics against a wide range of magnetic coupling without resorting to tight control and coil design. By introducing the concept and derivation principle for the coupling-insensitive compensation topologies, the X-type network is presented to provide self-regulation ability for primary coil current against variable coupling, thereby enabling steady power transfer in a highly dynamic environment. The design considerations for the passive parameters are elaborated, followed by the comparison with regular compensation methods. Owing to its unique structure and design flexibility, the X-type compensation exhibits a stable output characteristic that is beneficial in enhancing the tolerance to position shifts. Moreover, it also features a wide soft-switching range and more flexible design for the output level range than previous topologies. Experimental results show stable power transfer over a coupling factor of 0.14-0.28, where the power fluctuation is less than 20%. The presented method is seen as a potential solution for low power IPT systems, where high mobility is demanded.

Automated summary

The article introduces a primary-side X-type compensation topology for inductive power transfer systems to achieve stable power transfer against various magnetic coupling variations without the need for strict control and coil design. The X-type compensation provides stable output characteristics and enhanced tolerance to position shifts, suitable for low power IPT systems with high mobility demands.